Launching device for model airplanes



Feb. 1, 1966 J. BENSON LAUNCHING DEVICE FOR MODEL AIRPLANES 2 Sheets-Sheet 1 Filed July EL 1964 IN VE/V r02 Joseph L. 36175012 7M Mfifi 6m 55 Feb. 1, 1966 J- L. BENSON 3,232,564

LAUNCHING DEVICE FOR MODEL AIRPLANES Filed July 31. 1964 2 Sheets-Sheet 2 FIG, 4 FIG. 5'

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IN VENTOE Jose 2h L. 5612501 United States Patent 3,232,564 LAUNCHING DEVICE FOR MODEL ARPLANES Joseph L. Benson, 6850 S. Dorchester, Chicago, Ill. Filed July 31, 1964, Ser. No. 386,543 12 Claims. (Cl. 244-63) This invention relates to mechanisms to be used in association with model airplanes. In particular, the invention is concerned with the provision of launching means adapted to be employed in conjunction with model planes having gasoline powered engines and the like.

In most powered model airplane designs, control lines are employed for confining the flight of the plane. Thus, an individual flying the model will hold onto one end of the line while the other end is connected to the plane. When the plane is launched, the extent of its flight will be controlled by the length of the control lines. Movement of the plane to different vertical levels can be accomplished by various techniques including techniques wherein the operator moves his arm up and down and varies pressure on the line to cause the plane to assume different attitudes of flight.

Model airplane designs also provide arrangements wherein Wing flap movement and horizontal stabilizer movement can be accomplished by the operator. When such flap movements occur, the wind resistance will vary causing the plane to move through diflerent vertical levels.

Where model planes are provided with movable flaps, experience has shown that certain positions of these flaps are best suited for take-off. Thus, the operator, after starting of the model, manipulates the control lines to place the flaps in proper position. The plane is then released and, if the flaps are in proper position, more suitable take-otf conditions are provided.

It is extremely diflicult for an operator to determine the exact position of the flaps whereby the proper time for release of the plane can be determined. It is, accordingly, one object of this invention to provide an improved mechanism adapted to enable a model plane operator to precisely determine proper conditions for take-oft.

It is a further object of this invention to provide a launching device for model airplanes which embodies means which are operated through direct contact with movable flaps of a model airplane and which are conveniently released from contact with the plane whereby smooth take-off conditions can be provided.

These and other objects or" this invention will appear hereinafter and for purposes of illustration but not of limitation, specific embodiments of this invention are shown in the accompanying drawings in which:

FIGURE 1 is a vertical elevational view of the launching device of this invention;

FIGURE 2 is an enlarged detail view taken about the line 22 of FIGURE 1;

FIGURE 3 is an enlarged detail view taken about the line 3-3 of FIGURE 1;

FIGURE 4 is a vertical sectional view of the launching device taken about the line H of FIGURE 1;

FIGURE 5 is a top view of the launchingdevice shown in FIGURE 1;

FIGURE 6 is a schematic illustration of a model plane and associated control means;

FIGURE 7 is an enlarged detail view taken about the line 77 of FIGURE 1; and,

FIGURE 8 is an enlarged detail view taken about the line 8-8 of FIGURE 1.

The launching device of this invention comprises a frame portion having a first arm extending outwardly therefrom. Means are carried by this arm whichprovide for releasable connection of a model airplane to the launching device.

A second arm means is also associated with the launching device. One end of this arm means is pivotally connected to the device while the other end is adapted to be placed into contact with the movable flap of the horizontal stabilizer. Indicator means are operatively connected to this arm means and the position of the indicator means is-automatically adjusted in accordance with movements of the horizontal stabilizer which are transmitted through the second arm means. The indicator means contemplated herein are of a type which enables an operator to immediately determine when the proper attitude of the movable flaps has been reached. With this information, the plane can be easily released from the first arm and the contact means of the second arm are such that take-off can occur in a smooth operation without interference from either of these arm means.

FIGURES 1 and 4 illustrate the launching mechanism 10 of this invention. This mechanism comprises a main frame portion 12 which includes a pair of spaced-apart rear legs 14. A plate 16 is fastened to these legs, and this plate includes openings 18 whereby the frame can be secured to a member it) which may be any substantially stationary object. For example, a tool box can serve as the means for holding the frame in position during its use.

The forward legs 22 of the frame carry bracket means 24 and 26. These brackets include screw heads 23 and 30, respectively, whereby the brackets can be adjusted vertically relative to the legs 22.

An arm 32 is carried by the lower bracket 26. This lower bracket includes an extension 34 and the end 36 of the arm 32 is secured to this extension by fastener 38. As best shown in FIGURE 7, the extension cornprises a U-shaped member while the end 36 of the arm 32 carries a means 40 which provides for joining of this end to the extension 34. It will be noted that the fastener 3% includes a nut member whereby the end portion 36 and the extension 34 can be adjusted relative to each other.

The arm 32 terminates in a bifurcated end 42 which is adapted to fit around the mounting 44 which carries the rear wheel 46 of the plane. When pin 48 is fitted into openings 59 defined by the bifurcated end portions, the plane can be held in position. It will be noted that a joint 52 is formed in the arm 34 whereby some flexibility is provided in this arm.

A plate 54 is attached at its lower endto the bracket 24. As best shown in FIGURE 8, the attachment of the plate is provided through a cylindrical member 56 which is secured on the back side of the plate. The member 56 defines a threaded recess 58 which receives the end of bolt member 60. A channel-shaped plate member 62 fits around the legs 22 so that when the bolt member 69 is tightened, the plate 54 will be held in position relative to the legs 22.

A second arm 64 includes a bent end portion 66 which is received in the bore of cylindrical member 56. A nut 68 is threaded onto end '70 of the portion 66; however, this nut is not tightened whereby pivotal movement of the arm 64 is made possible. It will be noted that the arm 64 is bent along its length so that it is not in the same vertical plane as the arm 32. This permits the arm 64- to avoid interference with the vertical stabilizer of the plane for reasons which will become apparent.

FIGURES l and 6 illustrate portions of a model airplane 72 which is adapted to be launched through the use of the device of this invention. In a plane of .the type shown, control wires 74 and 76 extend to the inside of the fuselage where they are attached to a bell crank 78. The bell crank is in turn attached to rod 80 which extends to arm 82 at the rear of the plane. The arm 82 is rigidly attached to a fork member 84 with the prongs S6 of the fork being embedded in the flap 38 of the horizontal stabilizer.

The operator of the plane can grasp handle 90 to thereby fly the plane in a circle with the control wires 7 4 and '76 comprising the radius of the circle. It will be appreciated that movement of the wires 74 and 76 relative to each other will result in pivoting of the bell crank 1 8. This will in turn result in movement of the flaps 88 due to the linkage provided by the rod 86 and fork 84. In many instances, suitable linkage is also provided between the bell crank 73 and wing flaps 91 although this operation is not critical insofar as the instant invention is concerned.

As noted in FIGURE 1, the upper arm 64 carries a freely rotating roller 92 at its outer end. This roller 92 rides on the upper surface of the lateral flaps 88 and, accordingly, movement of these lateral flaps will result in pivoting of the arm 64. Also attached to thearm 64 is a plate 94-, this plate riding in contact with the surface of the plate 54. The plate 54 is provided with a rectangular area 96 which is substantially of the same dimensions as the plate 94. Accordingly, when the plate 94- is pivoted to assume a vertical position, the area 96 will be covered by the plate.

The area 96 is painted or otherwise formed whereby its color will be in sharp contrast with the background of the plane 54. The exposed surface or" the plate 94 will also be in sharp contrast with the area 96, and preferably the plate 94 will be painted the same color as the background of the plate 54.

In the operation of the construction of this invention, the arm 32 is first attached to the mounting 44 as shown in FIGURE 1. Suitable adjustments can be made in the vertical position of the arm 32 and in the lateral extent of this arm. Accordingly, the mechanism will accommodate model planes of a wide variety of sizes and designs. The pin 48 is, of course, inserted in the openings 50 to provide for securernent of the plane to the launching device.

The operator of the model plane then manually positions the flaps 88 whereby they will be located in the precise position in which the flaps should be held for take-oil. With the flaps manually held in position, the position of the bracket 24 is adjusted so that the roller 92, when'resting in the flap 88, will bring the plate 94 directly over the area 96. The bracket 24 is tightened in the desired position, and thereafter the flaps 88 are allowed to fall to their normal position so that a condition such as shown in FIGURE 1 (solid lines) is achieved. It will be understood that once the launching device has been set for a particular plane, there is no need to make any further adjustments unless the operator desires a take-oil under different conditions. i

The motor of the plane is started, and the operator then assumes a position at the end of the lines '4 and 76. It will also be noted that a line 98 is connected to the pin 48, and this line is of approximately the same length as the lines 74 and 76 whereby the operator can hold all three lines preparatory to launching. It will be understood that the lines are much longer, relative to the size of the plane, than is suggested by the illustrations in the drawing.

By manipulating the handle 90, the operator can change the attitude of the flaps 83. Accordingly, the plate 94 will be pivoted, and by observing the area 96, the operator can readily tell when this area has been obscured by the plate. The operator will then know that the flaps are in proper position for take-ofi. The operator can then simply pull on the line 93 releasing the pin 48 and thereby launch the plane in an extremely simple manner.

It will be understood that the linkage between the bell crank 78 and the wing flaps 99 also brings these flaps into proper position as a necessary incident to the positioning of the flaps 83. p

It will be noted that a flag 100 mounted on stall 102 is rotatably retained in the frame of the launching device 10. A plate 194 marked with directions enables the operator to determine wind direction and this arrangement also permits setting of the plane in a proper position relative to the wind direction.

It will be appreciated that the launching device described provides many features which are extremely valuable for carrying out the launching of model planes. The device combines a simple means for holding the plane in position while the operator is standing at some distance from the plane. The device also provides an extremely simple means for observing the proper attitude of the plane whereby launching can be accomplished in a desired fashion and whereby the plane can be launched several times without changingthe pattern of the launch.

The roller 92 can be permanently mounted on the arm 64 but it is preferred to provide a threaded end 106 on this arm whereby the extension 163 of the roller mount I can be removably attached. With this arrangement rollers of diiferent size can be employed for different size models. This is particularly important in the case of large models where a small roller might prevent clearance.

In considering the roller structure, it should also be noted that the roller includes resilient outer portion 110 and a solid inner portion 112. The inner portion can be a weighted member to insure proper contact with the flap 3% and in this connection, it will be appreciated that larger weights will be more suitable for larger models. I It will also be noted that the provision of the roller 92 and the location of contact of this roller completely obviates any possibility of damaging the plane during a launching operation. The roller will roll easily oil the stabilizer flaps 88 and there will be no interference which would tend to damage the plane or disrupt the proper take-ofi? conditions.

It will be understood that various changes and modifications can be made in the construction of this invention which provide the characteristics of this invention without departing from the spirit thereof particularly as defined in the following claims.

That which is claimed is:

1. A model airplane launching device comprising a frame member and means for supporting said frame memher in a stationary position on the ground whereby an airplane can be positioned adjacent thereto, holding means comprising a first arm on saidframe member extending laterally outwardly therefrom, means on said first arm for releasably securing an airplane thereto, a second arm pivotally connected at one end to said frame member, means at the other end of said second arm adapted to be brought into engagement with a movable flap on the'horizontal stabilizer on said plane, means defining a visible background surface, substantially opaque means operatively connected to said second arm and adapted to move across said surface in response to pivoting movement of said second arm, a portion of said surface being of contrasting color relative to the remainder of said surface whereby said opaque means connected to said second arin is adapted to obscure at least part of said contrasting portion in the course of its movement in response to variations in position of said movable flap, and means for releasing said holding means, said last mentioned means being operable independently of the position of said flap.

2. An apparatus in accordance with claim 1 wherein said frame defines leg members and including bracket means connecting said first and second arms to said leg means, said bracket means permitting adjustment of the positioning of said arms along said bracket means.

3. An apparatus in accordance with claim 2 including means for adjusting the length of said first arm.

4. In a model airplane launching device for use with model airplanes of the type including a bell crank memher associated with the plane, control wires connected to the bell crank member adapted to pivot the member, and linkage means connected to the bell crank member and to movable flaps in the plane whereby pivoting of the bell crank member will result in pivoting of the flaps about a horizontal axis, the improvement comprising a frame member for said launching device, a first arm extending laterally outwardly from said frame member and having means associated therewith for releasably securing said plane thereto, a second arm extending laterally outwardly from said frame member and having means thereon for engaging the upper surface of at least one of said flaps, said second arm being pivotally connected to said frame and having a first plate member attached thereto, a second larger plate member situated behind said first plate member whereby movement of said second arm will cause said first plate member to move across the surface of said second plate member, a portion on said second plate member having a color contrast relative to the remainder of said second plate member, and said first plate member being dimensioned to substantially obscure said portion of color contrast when pivoted to a position covering said portion, whereby pivotal movement of the flap engaged by said second arm will result in movement of said first plate member to achieve covering of said portion of color contrast.

5. An apparatus in accordance with claim 4 wherein said first arm is connected to the tail of said plane and wherein said second arm is located in contacting engagement with a flap on the horizontal stabilizer of said plane.

6. An apparatus in accordance with claim 4 wherein said frame defines leg members and including bracket means connecting said first and second arms to said leg means, said bracket means permitting adjustment of the positioning of said arms along said bracket means.

7. An apparatus in accordance with claim 4 including means for adjusting the length of said first arm.

8. An apparatus in accordance with claim 5 wherein a roller means is connected to the outer end of said second arm, said roller means providing the contacting relationship with said fiap.

9. An apparatus in accordance with claim 4 wherein the outer end of said first arm defines a bifurcated portion, and openings defined by the legs of said bifurcated portions whereby pin means can be moved into the openings to releasably hold said plane to said first arm.

10. An apparatus in accordance with claim 3 wherein said roller means is removably attached to said second arm so that different sizes of roller means can be employed.

11. An apparatus in accordance with claim 8 wherein said roller means comprises a resilient outer portion and a weighted inner portion.

12. A model airplane launching device comprising a. frame member and means for supporting said frame member in a stationary position on the ground or the like whereby a model airplane can be positioned adjacent thereto, holding means associated with said frame member, means on said holding means for releasably securing a model airplane thereto, an arm pivotally connected at one end to said frame member, means at the other end of said arm adapted to be brought into engagement with a movable flap on said plane, means assoclated with said frame member providing a visible background surface, substantially opaque means operatively connected to said arm and adapted to move across said surface in response to pivoting movement of said arm, a portion of said surface being of contrasting color relative to the remainder of said surface whereby said opaque means connected to said arm is adapted to obscure at least part of said contrasting portion in the course of its movement in response to variations in position of said movable flap, and means for releasing said holding means, said last mentioned means being operable independently of the position of said flap.

References Cited by the Examiner UNITED STATES PATENTS 3,154,883 11/1964 Gardella 24463 X MILTON BUCHLER, Primary Examiner. FERGUS S. MIDDLETON, Examiner. 

1. A MODEL AIRPLANE LAUNCHING DEVICE COMPRISING A FRAME MEMBER AND MEANS FOR SUPPORTING SAID FRAME MEMBER IN A STATIONARY POSITION ON THE GROUND WHEREBY AN AIRPLANE CAN BE POSITIONED ADJACENT THERETO, HOLDING MEANS COMPRISING A FIRST ARM ON SAID FRAME MEMBER EXTENDING LATERALLY OUTWARDLY THEREFROM, MEANS ON SAID FIRST ARM FOR RELEASABLY SECURING AN AIRPLANE THERETO, A SECOND ARM PIVOTALLY CONNECTED AT ONE END TO SAID FRAME MEMBER, MEANS AT THE OTHER END OF SAID SECOND ARM ADAPTED TO BE BROUGHT INTO ENGAGEMENT WITH A MOVABLE FLAP ON THE HORIZONTAL STABILIZER ON SAID PLANE, MEANS DEFINING A VISIBLE BACKGROUND SURFACE, SUBSTANTIALLY OPAQUE MEANS OPERATIVELY CONNECTED TO SAID SECOND ARM 